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The chiral metamaterials have been well applied in engineering applications, but the chiral structure of a single material is difficult to achieve low-frequency sound insulation or vibration reduction. Therefore, a new chiral lattice structure is proposed in this paper. Based on the Bloch's theorem, finite element analysis is carried out, and the energy band structures of different types of structures are calculated. The principle of band gap generation of Model No.1 is emphatically analyzed. The effect of geometric parameters on the band gap is discussed. In addition, the propagation characteristics of elastic waves with a specific frequency in the structure are explored. Finally, according to the corresponding relationship between the finite element simulation of vibration transmission in finite period structures and the band gap frequency range, it is verified that the structure can effectively restrain the vibration transmission. The research results show that the structure has excellent broadband gap performance in the frequency range of 3000 Hz, and has a certain filtering effect on vibration transmission. [ABSTRACT FROM AUTHOR]

In this paper, a new graded maze metamaterial with a single phase is proposed. Based on the finite element method and Bloch's theorem, the bandgap characteristics of graded maze structures in different regions are analyzed, and the mechanism of bandgap opening and closing is explored by vibration patterns. Subsequently, the mechanism of elastic wave propagation within different structures is comprehensively analyzed from four perspectives, such as group velocity and phase velocity. And the damping performance is further verified by frequency response spectra. The results show that the new structure has excellent low-frequency bandgap and damping performance, the local resonance of the graded maze plays an important role in the expansion of the bandgap, and there is directionality and regionality of wave propagation within the structure. This paper provides a new idea for wave propagation control and analysis, and low frequency damping of single-phase materials. • Low frequency bandgap generation through area grading. •Verification of bandgap and noise reduction performance by transfer function. •Analysis by group and phase velocity, iso-frequency and wave propagation maps. •Probing the bandgap opening mechanism by single cell vibration modal analysis. •Evaluation of vibration attenuation capacity with frequency-specific stress clouds. [ABSTRACT FROM AUTHOR]